Hormone Trials

Overview - The Hormone Trials consisted of two separate clinical trials in postmenopausal women ages 50 to 79 years at baseline:

• a trial of combined estrogen and progestin (Estrogen plus Progestin or E+P) in women who had an intact uterus at baseline (n=16,608); and

• a trial of estrogen (Estrogen Alone or E-Alone) in women who had a prior hysterectomy at baseline (n=10,739).

The trials began in 1994, with women being randomized between 1994 and 1998.  Following a WHI Data and Safety Monitoring Board (DSMB) review of the data to date, the E+P trial was stopped early in July 2002 when it was determined that the risks outweighed the benefits. The Estrogen-Alone trial was stopped early in March 2004, because an increased risk of stroke was found with no benefit for coronary heart disease.

While many of the publications from the Hormone Trials focus on the data collected from women in either the E+P Trial or the E-Alone Trial, some publications combined data for both hormone trials.  Here are summaries of findings from a few of those papers:

• Brain MRI

• Cardiovascular disease

Estrogen plus Progestin Trial

Overview - Participants with an intact uterus at baseline were randomized to one of two arms:

• Combined hormone therapy, consisting of 0.625 mg of conjugated equine estrogens plus 2.5 mg of medroxyprogesterone acetate daily (n=8506)

• Daily placebo pill (n=8102)

Findings - To learn more about some of the main findings from the Estrogen plus Progestin Trial, see these summaries of scientific publications:

• Principal findings

• Breast cancer after stopping

• 3-year follow-up

• Abnormal mammogram

• Symptom experience

• Venous thrombosis

• Diabetes

• Colorectal cancer

• Arterial disease

• Bone density

• Gynecological cancer

• Heart disease

• Breast cancer

• Cognitive function

• Stroke

• Quality of life

Additional Information -  Visit Questions and Answers about the WHI Estrogen plus Progestin Trial for additional details about the study and its findings.